Depopulation is a consolidated research topic and more recently it is also important for governments. In this context, we propose an alternative methodology of emerging patterns to reveal significant trends and nuances of the population decreasing in Spanish municipalities between 1998 and 2021. To this goal, we use conventional sources, such as the Municipal Register of Inhabitants. Our results demonstrate a cold-hot bipolar systemic behavior, more balanced in its surface dimension than in the demographic one. It confirms two realities north-south in the depopulating Spain. Cold spots are concentrated in the northern half of the country with intensifying and consecutive patterns. Finally, the study provides a scalable methodology that is replicable in other periods and/or territories.